Do you remember me telling you we are practicing non-verbal spells, Potter?" "Yes," said Harry stiffly. "Yes, sir." "There's no need to call me "sir" Professor." The words had escaped him before he knew what he was saying.
J. K. RowlingYOU CHEATING SCUM!โ Lee Jordan was howling into the megaphone, dancing out of Professor McGonagallโs reach. โYOU FILTHY, CHEATING B โโ Professor McGonagall didnโt even bother to tell him off. She was actually shaking her finger in Malfoyโs direction, her hat had fallen off, and she too was shouting furiously.
J. K. Rowling